1. Technical Field
The present invention relates to an imaging device, a method of adjusting color shift of a display monitor in an imaging device and a color shift adjuster of a display monitor.
2. Description of the Related Art
A liquid crystal display (hereinafter, referred to as an LCD) is widely used as an image display monitor of an imaging device such as a digital camera. The LCD represents colors based on the three primary colors of red, green and blue, and achieves a wide range of color reproducibility.
In a conventional display monitor, due to optical properties of a light guiding plate, a reflection plate, a color filter or the like, optical properties of an LED light source for use as backlight, or the like, colors of a subject image to be actually displayed on an LCD may be varied or shifted with respect to a subject image which is obtained when image input data is displayed on the LCD by truly reproducing the image input data.
If such a color shift occurs on an LCD, even if image information (red: 255, green: 255, blue: 255) corresponding to the brightest white of 256 gradation, for example, is input to a display monitor as image input data, such that a white image is displayed on the screen of the LCD, the white image becomes a yellowish white image, a reddish white image or the like.
A recent digital camera includes white balance, which adjusts an image displayed on a screen by a user while viewing the image on the screen, such that a shot white image, for example, white paper is displayed as a white object.
However, if such white balance is performed in a state in which colors are shifted on the LCD screen, extra white balance is performed by the color shift on the LCD, so that the color shift between the colors of the actual subject image and the colors of the image displayed on the LCD is not corrected. In this case, the white balance is not effectively performed. Even if a white image is displayed on the LCD screen, the image becomes a yellowish image or a reddish image if the image is displayed on a screen of a personal computer or the image is printed by a printer.
In order to improve such a color shift on a screen of an LCD, Japanese Patent Application Publication No. 2009-123489 discloses an invention in which a chromaticity range of illumination light is set within a target chromaticity range by combining a plurality of LED light sources each having a different chromaticity.
However, even if the color shift on the screen of the display monitor of the digital camera is adjusted before shipment, the color shift may occur due to some reasons after the shipment, for example, time degradation. The above-described prior art can not resolve such a problem.